The main aim of this proposal is to promote the basic methodology used for human embryonic stem cells (hESCs) culturing in order to encourage their large-scale growth in feeder layer-, animal- and serum-free conditions, and their distributions. In addition, we aim to further characterize these cells and to culture them under good laboratory practices (GLP) regulations. By achieving these goals, we will be able to distribute hESCs that will not only be suitable for basic studies but also potentially for clinical and industrial uses. To meet these aims our research team will concentrate on the following; [unreadable] Exploring the optimal culture conditions for hESCs: feeder layer-, animal- and serum-free conditions. [unreadable] Growing andpropagating hESCs inGLP. [unreadable] Generating a setof measurements for the evaluation ofthe cells' quality. [unreadable] Characterizing comprehensively the four Technion NIH-registered cells during their culture in various culture conditions, after prolonged culture and during early differentiation events. [unreadable] Improving the existing methods forfreezingandthawinghESCs. These improvements will constitute the ability to grow and propagate hESCs in large quantities in conditions that promote both research and clinical utilization of these cells.